...I think I can split up almost every ten digit number using a table of primes of 8 digits

There are 4,238,564 eight digit primes. There are 25 primes less than 100.

IF you multiply all eight digit primes by all two (and one) digit primes you get only over 105 million compound numbers. Minus the answers that appear as nine-digit results, you get about 100+ million ten digit numbers.(This does not include the 404+million 10 digit prime numbers.)

To get all ten-digit numbers made of two primes, you would need prime combinations of one digit and nine digits, one digit and ten digits, two digits and eight digits, three digits, and eight digits ... up to five digits and five digits.

The reason I ask about your computer, is because the results would take a huge amount of space on the computer. I would do it in stages using a six gig thumb drive. Then, copy the results off the thumb drive after each success. Sort them later.

I am not a millionaire either. But I have access to two computers. I was wondering if you were splitting the task between more than one computer.

For example one computer could resolve the EVEN 10 digit numbers between 2,000,000,014 and 9,999,999,874. Another computer could resolve the Even numbers between 1,000,000,0002 to 2,000,000,012.Because the first would be a 2 and a ten digit prime and there are 84,106,688 primes that would qualify..If you use a thumb drive for data and results, you could accomplish the first task in less than a day. (Depending on the speed and computer language you use. Using BASIC language my computer can do about 26,000 results in a second.)

Right! I get it now. He would need a two and 10 digit primes to test all the even numbers from 2,000,000,002 to 4,999,999,998. Likewise a single digit (odd) prime and a 10 digit prime for the odd numbers in range.

If you need to express a ten digit number as the sum of two primes, a list of primes up to NINE digits would suffice (except for 10 digit primes). You only need 50,847,534 primes to make a sum of all possible 10 digit compound numbers. That is available free online.

Calendar Magic is a tool for calendars. It has virtually all the calendars in use today. (Even Persian.)Calendar Magic also has a few Math tools. The program is available at download.cnet.com and I need to warn you that cnet now includes options to download toolbars and other useless bloatware with EVERY download. You download a program LINK. Then click on the link which starts the real download, and tries to entice you to add extras. Each is optional, but you need to read the screens and follow instructions to NOT download them. So, visit downloads.cnet.com and search for Calendar Magic. It works on the PC only.

I noticed that the program "Calendar Magic" now comes with math utilities. It is a free download.One of them is Prime Calculator. I typed in Saturday's date as "462013" and discovered it is a prime. Also, 4062013 is prime, if you prefer a leading zero.

So far there have been 10 prime days this year.192013, 1142013, 232013, 2112013, 2122013, 2272013, 322013, 372013, 3312013, and 462013.The next one is 492013. (Also 4092013, if you prefer a leading zero.)

Curious thing. After December 23, 2013, there will not be another prime-day until Thursday, January 5, 2017. That would be 1,108 days without a prime day.

I am not suggesting we stockpile primes, but it wouldn't hurt to keep some around when needed.